Study: diversity makes us psychotic

For every ten percentage point reduction in own-group density, the relative odds of reporting psychotic experiences increased 1.07 times (95% CI 1.01—1.14, P = 0.03 (trend)) for the total minority ethnic sample. In general, people living in areas of lower own-group density experienced greater social adversity that was in turn associated with reporting psychotic experiences.

What is the point of having nation-states at all if we are simply going to see every nation as being nothing more than a political agreement? Why retain the moniker "germany" or "italy" when you can be, "European Union Municipality 1 & European Union Municipality 2" ?